Valve mechanism for automatic train-pipe couplings



Aug. 26, 1930. u. A. WHITAKER VALVE MECHANISM FOR AUTOMATIC TRAIN PIPE GOUPLINGS Filed Dec. 14. 1928 .0 .www5

Patented 26,1930' e y l UNoAsA. WHiTAKER, oFjwuMERDI-NG, PENSYLVANIA, Assieironmof 4wrisrvnvof- OF ,PENNSYLVANIA vALvE MEoHivisi Fon AUroMe'lrIc. TRAIN-rire ooUPmims- Y,

" hppiiiafieireianecember 14,1928." srialLNo'. 326,039. y

l This vinvention relates 4to 1automaticV train pipe couplings, V'a'ndI'nore particularly to the type known asthe tight or'vrigi'dlock coupling. f n

Anl object of the invention is 'to provide av train pipe coupling of tlie above mentioned type With'fmean's for controlling the rovvof Athe fluid through1 the brake `pipe sofas to lpermit Vat least a sei"vicereduction when ythe couplingsfare" connectedre'gardless of the position of thehandl'eofthe brake, pipe anglecock.

"Anotherobject' of tlie invention is to KVprov 'i vide a train pipe coupling ofthe above men'- tioned typewithrneans which the c'halrgV ing of. an "empty section of train 'fr'om* a bharged section Will bege'ffected'Without c' ,causing an vemergency applicationfon,the:

charged section. l Y 2o Another object of the-inventionis to pro'- vi-de :valve ymechanisms for .an-f automatic train pipe vcoupling vvhr'ereinv alconduit 'in the' coupling head Which-is connected to "the Y 1 brake pipe is also connected tothe brake pipe by a secondk conduit constitutingfa bye pass' Varound aV valvey in. the brake; pipe, `.the

by-pass containing *an* automatically "operi yated valve device adapted tof controlA comy I'nunication through'Y the conduit vvhen the bralepipe valve is closed] K Y Y Y, e Another object of the invention is to proi vide a train pipe coupling of thecharacter mentioned which is simple in construction, and reliable and eXact in function under all f conditions of service. 'f Y The invention alsov comprises certain new and useful improvements in the construction, arrangement and combination "of the sev eral vparts 'of' Whicht lis composedfas Will f n the accompanying drawings; 'v Figure 1 isa Alongitudinal -sectionof an; vautomatic train pipe c'cupling-embodying the invenftion, showing the same coupled toa counter-` part coupling; 1Figi-'Qis a section of the robe hereinafter morel fully fdescllfvbd'l l `tary valve device .shown in l Figg` 1,l shovv.

ing the valve thereofpositioned to effectthe closing Vofthe brake pipe by-passvvalvedef vice When the couplings are being coupled; n

andvc-Figfqis' asection takeni'on y the line i 'Trainspipe Y couplings of.; the typelnoWn as the *tight orl rigid lock coupling, are

shwnV forv vexample in the "Westinghouse Patent No. 708,747-, dated-September f 9, 11902, 'and in Which each-coupling. head is yprovided vvithl a laterally projecting hookeshaped portionA adapted'to engage the corresponding portion o' a counterpart coupling by .a relatively lateral movement, Yand be Vrigidly locked together by cam leversfor latches, one Y* pivoted on V'each couplinghead andbearing Y against the other counterpart coupling'head. Train,v pipe passages "are in the V"clPlng tolfabut against Vcorresponding gaskets of fc5v j 'heads and are Provided W'li gaskets adapted the counterpartcouplingfhead when the tvvo l* p are connected together. 1,. l

automatiea'llyY couplezflvvith'a counterpart v'cjouplingvvhen tvvfo cars 'are 'brughtftoy' gether, itl is necessary to. manually operate thetrainpipe valvesto ,charge an'einpty Sec;

'ftioniofv'trainfrom-a chargedsectionV yBy the present invention-f,l means* are'fpro viager@ auamaiCaHyby-paeeing the brake pipe angiegeoekfwilenvui@ Coupling isbeing 'l r coupled toafc'ounterpartf coup'iling` so lthat When an empty section v of train is connected to a charged section the -fluid ilovvingi-nto the unchargedsection will be."v atv vsuoli a irate as to vpreventan emergency Vapplicationc of the brakesmon.'thelcharged section. Y Referring to thedr'awings, automatic l as Y trainvpipe Acoupling,'head 5:comprises, a pro#y jectingnose adapted to engage inv a'recess 7 'fl a i anatema-Coupling beaux ,z Anvers, pivoadin um Coupling head-5 at 9, has a camA face l0 'for engaging the Yface l'lf'ofV a counterpart coupling head, to lock theYK tvvo coupling heads together -vvhei'the Smeer@ Curled. in the' mlrijr Sheri/effin.

vided With'r afhead'l, andfinterposed between said-head' andv4 is a coil spring 17. s f v grimiever'-fefearrislannif-12; rewhieh l a' 'rod' 13 is pivotally connected[by .af pin"` 14. 'The outer end of: the -rodl 13 Vispro- Y rlhe rear end of the coupling head 11 is formed with a tubular extension 18 which constitutes a guide for the forward end of a stem19.

The stem 19y has its rear `end provided with a ball section 2 0 adapted to be mounted in a socket (not shown) carried by the car.

The tubular extension 18 is provided with -diametrically disposed longitudinal's'lots .21

"intowhichextend the projectingends ofav pino-22 whichis passed transversely through the stem 19.. y v

A coil spring 23`encircles the stem 19 and the tubular extension 18, one end of the spring bearing against a flange 24 formed on the inner end of the coupling ghead, while with an extended portion 26, .y on which aroller 27 is .mounted by means of a pin 28..

`The roller 27 is disposed valong the longitudinal lcenter line` of the stem and it is adapted to be engaged by the hook-shaped end29 of an arm30 extending from the y lever 8.

f I when' the epupiingjheadfisemplea with a f counterpart coupling, the spring 17 will forcejthe cam surface y10 of the lever 8 tightly into engagement with the surface 11 of the counterpart ycoupling and the end k29 of the arm 30 will be disengaged fromthe roller 27 However, when thecars are uncoupled; andVK the .couplings` separate, the spring 23 will force the coupling head outwardlyA on the stemr19, thereby bringing the cam surface 31 on the end 29 of the arm 30 into contact with the roller27.

The extremity of the arm 30is formedy with an. arcuate recess 32 into which the roller 27 seatswhenthe coupling head 5 is moved outwardly with respect to the stem when the coupling is beinguncoupled. In this vway the lever 8 will., be retained inits innermost yposition within the coupling head and it will be disposed out of the path of the nose6 ofa counterpart coupling head. For the purpose oflimiting the outward movement of the lever 8, the coupling head isprovided with a lug 33 againstwhich the arm 3() may strike, should the interlock provided when .the roller 27 is positioned in the recess32 be detached when the coupling head is unooupled.

The vbrake pipe 35. is connected to one l end of a conduit 36 with which the coupling head 5 is provided.

The front or nose end of the conduit 36, carries a gasket 37 adapted to engage the corresponding gasket on a Vcounterpart coupling head and make a fluid tight joint when the couplings are connected together.

The forward portion of the conduit 36 is enclosed by a tubular casing 38 containing an YeXpansible coil spring 39, one end of which bears against a collar 40 carried by the Vcasing V38, while the other end thereof bears against a sleeve l1 encircling-the end portion of the conduit 36 adjacent to the gasket 37.

The sleeve 11, carries a plurality of pins 42 which project inwardly therefrom. The eX- tremity of each pinis disposed within a slot .43 formed on the exterior of the conduit 36.

` The4` pressure exerted -by the `spring 39 against the sleeve 11 normally retains the pins 42 in engagement with a step or Yshoulder 141 formed on the exterior of the conduit 36 at the end of the slots 43. In this way the abutting. gaskets 37 of the two coupling heads will be held tightly 'together irrespective of the relative movements of the coupling-heads ,when the cars are in motion, as will be understood.

rMountedin a chamber 4C6- formed in the brakepipe 35 is an angle cock device ccmprising ay plug valve 47 Vhaving a port 0r r waterway d8. adapted vt0 register with the brake pipe.passage when the valve is fully o opened. to permit an unrestricted flow of fluid therethrough.

A rfhe plug valve 47 has a handle or arm 49 which isv adapted to be actuated by the rod V5()v of apiston 51 mounted in a cylinder 52'. rlhe piston rod 50 is guided by a boss 53 formed in the end of the cylinder 52.

A seat rib .54 is formed on the end face of 1.

the boss y53,.against which a valve 55 on the piston51 rests, when the piston is at one end of its stroke.y V

This piston l51 is forced away from the seat rib 54 by a coil spring 56,` which encircles the boss 53, one end of the spring bearing against the piston, and the opposite end of the spring bearing against the endv wall of the .c ylinderf52.

A chamber 57 on the side of the piston 51 opposite to the spring 56, is connected to the signal pipe 341 by a pipe 58, and in order to permit .venting of the signal pipe and the cylinder 57 when the cars are coupled, the pipe 58 is provided with a valve 59 adapted, upon operation, to vent the pipe 58 brought together for coupling up to.' establish communication from the brake: pipe to ythe 'conduit 36 before the plugvalve-e? has been opened;

Y The valve .device .61 includes a diaphragm. .62 Which is `niountedin the valve; casing Afor movement tovvard'andavvay from a seat rib -69 projectingintoa `clfiambei" 63. The chamber,- 63 is connected; tothe conduit 60, andv is ialso connectedtothe conduit`36 through a passage 67 having a. restrictedaportion 68 .thereintoprovide -a choke. The seatfrib i 69r surrounds thepassage 67 so that yWhen `th'ediaphragin is iinseated therefrom, fluid .under pressure delivered to chamber (3331"10111- f the brake vpipe through conduit 60, Will be permitted to lovvfthiough passage 67 into .conduit 36, the .restricted opening 68 restraining the amount of fluid flowing into rthe conduit' 60 for a purpose to be herein-` Y after described. j v

.i Thechamber. 63 is in communication vvithv iachamberja, on the other side of the. dia-k phragms62, through la;passa',g`;e"65 having. a

restricted:l Aportion therein to` provide a choke. o

. When the coupling head iseoupled to a counterpart coupling, v'the diaphragmV 62 Will beunseatedVV from` the seat rib 69,1- and `vWill `vvith ports 103 and. 104 and portsi105 andv .beV seated 'against a seat rib 70 so as tocl'ose tlie chamber '64 from a;chamber Y71 of less v area. ,The `portion of the ,diaphragmfdis-` inchainber 63. 1.

posed Within thegseat rib `Carries Va yhead Thev iiuted stein 73 rof a 4valve 74l'ieXtends through an opening-75m a Wall y76 separat-1 ing the chamberi71: from' a chamber??- and bears against the head 72; Aiseat 78. is formed in the Wall 7 6l for thevalve 74.; The chamber 77 is open .tov the a-tmosph'ere through an o eniiiff 79. Mounted in chant,-

D p P3 bei' 77 is an expansible coil spring 80 Which bears against the head of thev'alve Pfand maintains the stem 73 in contact With the head 72. f

Mounted in chamber 71 and-encircling the the seat rib 70 againstfthepressure of fluid' Inasinuchas chamber 7-1 .Will v be tov the atmosphere through opening 75,.'chai`nber :775 andY opening `79 rvwhen thefcoupliiigs arev connected, the portion of the" diaphragm 62 outsideof kthe seatrib` 70 Will belbalanced, clue Lto ithe 'free' communication through passage 65 to both sides thereof, but

since the varea-fof the vrdiaphragm inside of .seat rib 170is exposed to. atmospheric pres' `116 is connected to shaft 117 sure,`the 'fluidv under pressureffin chambery 63 Will maintain the .diaphragm against seat The valve'll a luted steinA ivvliich.V i

extendsthrough anopening 88 formed in a Wall89 separating the cliainber-85froin a ,chanibery Q90 and;y engagesthe-head of a plunger 91. f

The sha-nkfofthfe' plungerf91lis p in an opening 92 formed' in'l'theouter-end e Wvall 93,V and the extremity of the ,plunger abuts a lug` 941:r on' thecounterpart coupling heady When the l:couplings arev4 coupled.. togetlierl so as to unseat thevalve 84.

Chamber v is vented to the atmosphere Y longi- Y through a `leakage groove 95 yforin'ed tudinally yof the opening 92.

v An' expansible coii spring 96 1s mountedv yin ythe chamber 85 andbears against the .e

head of .valvet [This springv is adapted; vto forceitlie valve to .its Seat when 'the couplings are being uncoupled, so as to 'pre-v vent thefpassage of uid,from` chambe'r' 'intochainbeil 90.- i.

fassociaieci with tils-miaro'iiing avass is a rotaryvalve device A98 havingka chainloeif-j 7 99 containingarotary valve 100.

l 'The valve 1,00- is provided With cavities 101 and 102 which areadapted to register 106 respectively, in the seat 107 of the valve. The port 103 isconnected to `areservoir 108 by a pipev 109, vvhile the port104` is con#l .10a and 104 ksonas the feservQ-irioswiube; Icharged fromthe ,brake pipe 35;,5vlien lthe 1 vcouplingheadsv are ycoupled together,

l Chamber M90 Vi's connected' to. afrestrictedf 11bV s passage 112, pipe 1111, lport 106, andcavity s 102 inthe Arotary `valve 100, with atmosl" pheric exhaust port 105.

VYTll rotary Valve 100" has a .Shaft n 115 which is connected vto the car coupling pin 114 through :a plurality of shafts 115,116 and 117, arranged lin vvertical alineinent, shaft 117 being-connected tothe end ofthe coupler pin 114; A

Shaft `115 is connectedV to the shaft iso byeni'ean's of a universal joint 1.18, andshaft type of jointv 119.

Interposedfbetiveen the endsY of shafts and` 116 is a telescoping" section 12,0 Which permits raising and lovvering movement of.

the car coupling and the tr'ain'pipe coupling heads relative to one another andV also vvertical inovementvof'the` coupling pin lltand shaft 117`relativegto shaft 113. The u ni-y by a similar versalk joints 118 and 119 allow for angular movement between the car and train pipe coupling head. 1

The coupling pin 114 terminates within a casing`121` depending from the car coupler 122. The end of the coupling pin 114 has a flange 123 fixed thereto, against which bears one end of an expansible coil spring 124 which encircles the coupling' pin 114 and is adapted to force the same downwardly. l

The shaft 117 is slidablyand. rotatably mounted in the casing 121. Spiral grooves 125 Vare formedin the shaft 117 and receive tongues 126 formed on the casing 121, yso

that when the shaft 117 is raised with the Y coupling pin 114, in the mannerv to be heref inafter described, it will be rotated.

` will lift the shaft 117.A

In operation, when it is desired to separate two cars of a train having the brake pipe charged with fluid under pressure, the valve 59 is turned to the position by which Vthe fluid in the signal pipe 34 and the chamber 57 will be exhausted to the atmosphere, andthe coupling pin 114 is raised through the .usual` mechanism (not shown), which `When thekr pressure of 4the fluid in the chamber 57 is reduced a predetermined amount, the spring 56 will force the piston 51 outwardly, thereby withdrawing the end of the rod from 'the arm'49 of the plug `valve 47.

will be permitted to flow'from thebrale pipeV through conduit'60, lchamber 63, passage `67, and choke 68, into the conduit 36, until the diaphragm 62' is `moved, in the manner to be hereinafter described,

vfrom the seat rib and seated against the seat rib 69 to shut off` communication from thev conduit 60 to thek conduit 36.

' When the coupling pin 114 is raised to unlatch the car couplers, and the shaft 117 is also raised by said pin, theshaft 117, dur- :ing its kupward movement, lwill be rotated through the medium of the spiral grooves 125 and the tongues 126. The turning of the shaft 117 is ltransmitted through the universal joint 119, to shaft 116, which in turn transmitsv the rotary `movement through the vltelescopic connection 1.20 to shaft 115, and thence through the universal joint 118 to the shaft 113 of the rotary valve 100.v

lll/Then the rotary valve 100 is thus-rotated,

the `cavity 101 will be moved from the ports 103 and 104 and the cavity 102 will be moved from the ports 105'and .106, the angle of rotation of the valve 100 Vbeingrsuflicient to connect the port 103 to the port 106 through a cavity127 (see Fig. 2). y

lnasmuch as the pressure of the fluidin the reservoir 108 will be substantially equal to the pressure of the fluidin the brake pipe 35 when the coupling heads 5 are connected, when the cars are lbeing uncoupled and port104 has been closedin the manner just described, Huid from the reservoir 108, flowing through the rotary valve device .'98, willl pass through port '106, pipe 111 and restricted opening 112 and Aenter chamber 90 of the controlling device 83. As the valve 34 will be unseated, the fluid delivered to chamber 90 from the reservoir 108 will iiow'through openings 88 into chamber 85, and will thence flow through conduit 86 to chamber V71.

Obviously some of the fluid entering chamber 90 will pass to the atmosphere through groove-95, and also some of the fluid entering chamber 71 will pass .to the atmosphere throughopening 75, chamber V7 7 and opening 79, because valve 74 will be unseated, as shown in Fig. 1 but the amount of fiuid lost to the atmosphere through ythese two atmosphericv openings is not suiiicient to prevent a build up of the pressure in chamber 71.

1When the 'fluid pressure is thus built up in chamber 71 an amount sufficient to balance the pressure of the fluid on the other side of the diaphragm y62, the force exerted by spring 81 will be sufficient to move the diaphragm 62 from the seat rib 70 and seat the same against the seat rib 69, against the pressure ofthe fluid in chamber 63. This will cut off communication romconduit 60 to the conduit 36.

l/Vhen the cars are uncoupled, the train pipe couplings will remain coupled and locked together until the cars have moved apart sufliciently to pull the coupling heads 5 outwardly of the stems 19, and further longitudinal movement is prevented by the pins 22 engaging the ends of the slots 21.

This action will move the ends 29 of the arms 30 toward the extremities of the portions 26 of the stems. l/"hen the cam surfaces 31 engage the rollers 27, the .arms 30 will be caused to move laterally of the stemsuntil the rollers 27 engage in the recesses 32. rlhe cam surfaces 10 of the levers 8 will thus be withdrawn from the faces 11 of the coupling heads, and Athe couplings will be unlocked.

The movement of the diaphragm 62 from the seat rib 7 0 to the seat rib 69 heretofore 'described adapted: to" be `effected l, before the lug 94 onthe counterpart coupling ,head has moved away from the Iend of l' the. plunger 91 whenthec'oupling heads separate andthe abutting gaskets' 37 are pulled apart. 1

When the lug 94 movesawayf from the end Y of the plunger 91 as the coupling heads are uncoupled, the spring96 will vforce the valvel 84 to its seat, andltherefore,the` fluid entering chamber 90 from the` reservoir y108 willy pass to Vthe atmosphere through leakage groove 95. u t y ff L After the coupling heads vseparatefA the valve 59 can be vturnedto cutoff fthe vent'to the atmosphereA for' 'the signal pipev .34* and the cylinder 57..v j

,On the other` handpinfcoupling a section of train having an uncharged brake pipe to a section having a charged brake pipe, when the cars are brought together forcoupling up, ,the impact of the two coupling-heads comingfftogetherwill. move the ycoupling head 5 rearwardly on thestem 19,'` and this When thedcoupling heads 5 comeltogether vfor coupling` up, the endof` theplungerv 91' will` engage the lug 94.0f the. counterpart couplingghead. This action Lwill unseaty the valve 84 and hence'the fluid in the chambers 64and 7 1 of the coupling head at 'the'.fend'of the charged-section of .bralzel'pipe lwill-be vented to the atmosphere through conduit Y 86, chamber 85, opening S8 and groove 95.

When the pressurefof the fluid in chambers 64 and 71 is reduced by the escape of'v the liuidthrough groove 95, the pressure of the fluid in chamber 63 will force the dia,- phragm 62 away from the seat `rib 69 and V will seat the same against the seat rib 70.

This action can be timed to takeiplace immediately' after the gaskets 37 have been brought together so lthat brake pipe pressure can be built yup in the uncharged section of brake pipe. Y Y In devices of the type herein shown and described, it is of advantage tok limit the rate of reduction in brake pipe pressure in va charged section when the charged section is coupled to anuncharged section so as lto lprevent a too rapid reduction of the pressure in the charged section andthereby prevent undesired emergency action therein. y

Accordingly', `when the train pipe coupling vrheads V5 vhave Abeen coupled in' the manner describedfand the diaphragm '62fhas 'been-unseated from y.the seat ribv 69-V andA the ends-of passage 67 exposed, the `brake* pipe e--fluid ywill bypas'saround thel closed plug valve 47 ,fand ilow'th'rough conduit-60 into chamber63,

andthen' through thegchoke 68' in passage '67 into the noseendofrthe conduit 36, and

thenceinto .thev conduit 36 ofthe coupling 'at the end ofthe uncharged section, thev re! stricted` rate of flow-'gradually building the pressure in the.v unch'arged section.

Afterfthe `train .pipecoupling' heads 5 havebeencoupled', the pressureof the fluid in the signal pipe 34 isbuilt up in the customary manner, and the pressure willbe 'alsobuilt up'in chamber 57 ,as the latteris i directly connected vto the signal pipe. n n' ti :When'the pressure of the signal p ipe fluid '-buildsup a predetermined amount lin chamber 57, the piston 51''will be forced outwardly against. the pressure .exerted Vby spring 56. This action-will move thetip of l Vthe rod l50 into .engagement with thearm'49 and wconsequently continued outward rmovement of rthe piston' willV swing the arm. 49 'i fromleft to right, thereby rotating the.. plug valve 47 tol bring ytheport .48 into registration with the opening in the brake pipe 35:.

In this 'way unrestricted flow of the fluid throughtheladjoining conduits 36 rofthe coupling heads will not be had until after*V the conduits have been tightly connected together and a predetermined ainountfof prespipe yof sure has beenbuilt up inthe brake the uncharged section of 'train'. After the Icouplingl heads haveI been vbrought :together Vand communicationis es# tablishedV through the adj oining' conduits.` 36 so that fluid underpressure is delivered to the'k unchar'ged section-from the charged sec-. y f

tion, `and assumingl that the valve, V4,7*4 is closed, the 'diaphragmA 62 kof the coupling y' i head 5y ofthe unch'arged section will remain seated 'against thefseatfrib 69 until suicient pressure'has beenrbuilt up in the passage .67., inside of seat rib ,69 to force the ,diaphragm 62 from this seat.

Chambers 64 and 70 will'beiopenfto the y atmospherefthrough conduit S6, chamber 8.5, opening 88, v chamberf 90 "and vgroove 95,- inasmuch as valve 8 4 willv be. unseatedgwhen theicoupling heads are coupled together, as

shown in Fig. l. A'Iherefore only sulii'cient lpressure will have to be built up in the passage 67 toovercome the force exerted by seating thereof against the Vseat 4rib k7,0.' v After the diaphragm 62 of the 'coupling headatithe'end of the uncharged trainfsection has been yactuated to establish communilthe. spring 8l, to`cause the unseating .of the diaphragm` 62 from .l seat rib 69 .and the n cation from'the'conduit 36-to 'the conduit 60,--'V theiflui'd from the. lchargedrsectionrwill ami@ vflow -atl azfreduced rate through conduit 60 passage of the brake pipe 35, through the build up of suflcientpressure` in the signal pipe 34 and cylinder-5.? to: cause the piston 51 to be moved tothe outer end of its stroke in the manner heretofore described,

and *therefore* unrestricted vcommunication train, section .will be.` had after the pressure of the Huid admitted thereto trom the charged section has been increased'a [predetermined: amount. i Y

Assuming Vthat the valve 47 'of' they brake piper on the uncharged sectionv is. open; when the couplingKY head of. an unchargetdV section .isfconpled tof lthe Vcounterpart coupling of a ichargedvtrain: section, when communication is- -establislied between the adjoining conduits, as 'has beenfdescfribed, thelui'd flowingvfroan the Vcharged section-Will'be conducted' through `the conduitfzS/(' directly to.y kthe f brake pipeff 5., yp assing i through the port48 inthevalvell?. e c

When the pressure-"builds up;V in 4thebra-ke pipef of theuncharged,section=,`the 'pressure will also builtfup `inrcondnit 60, inasmuch vas this conduiitzisiin direct communication Withi the brake pipe, andv a build up of pressurein the: portion 'of' thechamber 63' outside of the seaty rib' 69` will also occur. The fluid, will also'oW` into chambers 64E and 70 through the restricted opening 66,

- but as chamber 70will Abe vented .to the atmosphere through conduit'86, chamber 85, opening 88, chamber 90 i and groove 95, the pressure willv not be vbuilt up in chambers 64 and 7 0- an amount equal'to the pressure built upinf chamber 63.` `Accordingly after the pressure has been built up-in chamber 63 apredetermined amount the diaphragm G9 will be forced fromztheseat ribl69 and will beseated ragainstseat ribv 70. 'In this way' communication Will be established I from conduitto chamberv?) and conduit 60, throughchoke 68 and passage 67, and as the seating ofthe diaphragm 62V against the seat'l'ib 70 Will cut off thecommunication between chambers 645 andfl, urtherfloss of fluid romthedevicefvvifll be prevented.

"l-helast cary of a train having couplings otthetypeherein vshown and described, should havei dummy couplings applied' to the open endsof theL train pipes to'close'the same.v Any' suitable `type Vof Ydummy coupling be employed. These dummy couplings arenecessary because-the signal pipe yWill charged`v land hence Vthe yplug valve 47' -Wiflll be opened through-1 the 1 action ofA the 1 pistoni as will be understood;

4 Vllhile one illustrativaembodiment otithe: inventionr basi boem described iin detail, it isA not my intention to limitits scope tofthat embodiment or otherwise` than by thev terms of the appended claims.

Having novv described my invention, What I claim as new and desire to secure by Letters Patent, is

l. The combination With a brake pipe, of a coupling having a conduit communicating- With said brake pipe, a valve for controlling communication through the brakepipe, means actuated upon the coming together of theL coupling with a counterpart coupling for operating the valve to open the same, a second conduit constituting ahy-pass around the valve, 'means for permitting fluid to iiow through the by-pass when the valve is closed, and means. actuated upon the coming together of the coupling With a counterpart coupling for controlling the operation of said by-pass control means.

2. The' combination With a brake pipe, of a coupling having a conduit'communicating With said brake pipe, a valvelfor'controlling communication through the brake pipe,a second-conduit constituting-'a by-pass around the valve, meansv orcutting oil communication through the'by-pass Whenl the coupling is uncoupled, and meansI automatically actuated uponthe comilng'togetlrierfof the coupling With a counterpart cougpli-ngfo'r establishing communication'through the by-pass.

3. The combination With a brake pipe, of acouplinghaving a conduit communicating With said brake pipe, a valve for controlling communication through the brake pipe, a by-pass around the valve, means for restricting the flow of iii-iid from the bypass to the conduit, and means 'for auto? matically'closing the by-pass When the coupling is separated 'from a counterpart coupling;

In testimony vvhereoff have hereunto set my hand, this 8thday of December, 1928.

'UNCAS A. 'WHTAKER 

